Seat assembly having an air plenum member

ABSTRACT

A seat assembly includes a seat cushion having a recess, and an air plenum member disposed in the recess for routing air through at least a portion of the seat cushion. The air plenum member has a first portion that comprises foam, and a second portion that is attached to the first portion and that comprises a polyolefin sheet. The seat assembly further includes a cover layer covering the air plenum member and the seat cushion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a seat assembly having an air plenum member, and to a method of making such a seat assembly.

2. Background Art

A seat assembly may be provided with an air distribution system for routing air through the seat assembly. For example, one known seat assembly includes an air plenum positioned in a foam seat cushion. The air plenum has a top polyester scrim layer adhesively attached to a bottom foam base. The scrim layer includes a polyester mesh attached to a polyester film, and adhesive material for attaching the scrim layer to the foam base. The scrim layer further has multiple apertures for allowing air to pass through the scrim layer.

SUMMARY OF THE INVENTION

Under the invention, a seat assembly for use with a motor vehicle is provided. In one embodiment, the seat assembly includes a seat cushion having a recess, and an air plenum member disposed in the recess for routing air through at least a portion of the seat cushion. The air plenum member has a first portion that comprises foam, and a second portion that is attached to the first portion and that comprises a polyolefin sheet. The seat assembly further includes a cover layer covering the air plenum member and the seat cushion.

In another embodiment, the seat assembly includes a seat cushion having a recess, and an air plenum member disposed in the recess for routing air through at least a portion of the seat cushion. The air plenum member has a first portion that comprises foam, and a second portion that comprises a plastic sheet heat staked to the first portion such that the second portion is fused with the first portion, thereby forming a seal along at least a portion of a junction of the first and second portions. The seat assembly further includes a cover layer covering the air plenum member and the seat cushion.

Further under the invention, a method of making a seat assembly is provided. The method includes the steps of positioning together first and second portions of an air plenum member, the first portion comprising foam and the second portion comprising a plastic sheet; heat bonding the second portion to the first portion such that a seal is formed along at least a portion of a junction of the first and second portions; positioning the air plenum member in a recess of a seat cushion; and positioning a cover layer over the air plenum member and the seat cushion. Moreover, the air plenum member is configured to route air through at least a portion of the seat cushion.

While exemplary embodiments in accordance with the invention are illustrated and disclosed, such disclosure should not be construed to limit the claims. It is anticipated that various modifications and alternative designs may be made without departing from the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a seat assembly according to the invention, wherein the seat assembly includes a seat bottom and a seat back pivotally attached to the seat bottom;

FIG. 2 is an exploded perspective view of the seat bottom showing a support member, a seat cushion having a recess, an air plenum member that is disposable in the recess, and a trim cover for covering the seat cushion and air plenum member;

FIG. 3 is a cross-sectional view of the seat bottom taken along line 3-3 of FIG. 1 and viewed in the direction of the arrows;

FIG. 4 is an exploded perspective view of the air plenum member; and

FIG. 5 is a fragmentary cross-section view of the air plenum member.

DETAILED DESCRIPTION

FIG. 1 shows a seat assembly 10 according to the invention for use with a motor vehicle. The seat assembly 10 includes a seat bottom 12 and a seat back 14 pivotally connected to the seat bottom 12. In the embodiment shown in FIG. 1, the seat bottom 12 and seat back 14 are each provided with an air plenum member 16. Alternatively, the seat assembly 10 may be provided with a single air plenum member 16 positioned in either the seat bottom 12 or seat back 14.

Referring to FIGS. 1-4, a detailed description of the seat bottom 12 will now be provided, with the understanding that the seat back 14 may have the same or similar construction. As shown in FIGS. 2 and 3, the seat bottom 12 includes a support member 18, such as a seat pan and/or seat frame, a seat cushion 20 supported by the support member 18 and configured to receive the air plenum member 16, and a cover layer or trim cover 22 covering the air plenum member 16, support member 18 and seat cushion 20.

The seat cushion 20 may be made of any suitable material, such as foam, and includes a recess 24 formed therein for receiving the air plenum member 16. While the recess 24 may have any suitable configuration that corresponds to the configuration of the air plenum member 16, in the embodiment shown in FIG. 2, the recess 24 includes multiple trenches or channels 26. The seat cushion 18 may further include a duct or passage 28 through which air may pass. In the embodiment shown in FIGS. 2 and 3, the passage 28 extends from the recess 24 to a lower surface 30 of the seat cushion 20.

The air plenum member 16 is disposed in the recess 24 and is configured to route air through at least a portion of the seat cushion 20. For example, the air plenum member 16 may route temperature conditioned air and/or ambient air toward or away from the cover layer 22. As such, the air plenum member 16 may function as an air distribution device or an air collection device.

The air plenum member 16 may have any suitable configuration for routing air through the seat cushion 20. For example, the air plenum member 16 may have one or more legs or branches 32 that define one or more passages or channels 34 for directing air through the seat cushion 20. In the embodiment shown in FIGS. 1 and 2, the air plenum member 16 of the seat bottom 12 has a generally H-shaped configuration having multiple branches 32 extending from a main body 35. As other examples, the air plenum member 16 may have a generally U-shaped or X-shaped configuration.

Referring to FIGS. 2-4, the air plenum member 16 includes a foam first portion 36, such as a base or bottom portion, and a second portion 38, such as a cover or top portion, that comprises a flexible plastic sheet attached to the first portion 36 to form an air plenum or chamber. The first portion 36 may comprise any suitable foam, such as polyurethane foam or an expanded plastic, and the second portion 38 may comprise any suitable plastic sheet, such as a non-expanded polyolefin plastic sheet. In one embodiment, the second portion 38 comprises a plastic film, such as a polypropylene film having a thickness in the range of 0.1 to 0.4 inches. In another embodiment, the second portion 38 comprises a nonwoven plastic layer, such as a polypropylene nonwoven scrim layer having a thickness in the range of 0.005 to 0.01 inches. The second portion 38 also includes multiple apertures 39 for allowing air to pass through the second portion 38, which may be otherwise air-impermeable.

While the second portion 38 may be attached to the first portion 36 in any suitable manner, such as with an adhesive, in one embodiment, the second portion 38 is heat staked or heat bonded to the first portion 36. For example, the second portion 38 may be vibration welded, sonic welded, or otherwise heat fused to a connection area, such as flange 40, of the first portion 36. Such an attachment means may provide a durable airtight seal along the entire junction, or at least a portion thereof, between the portions 36 and 38.

As mentioned above, the air plenum member 16 may be configured to route temperature conditioned air and/or ambient air toward or away from the trim cover 22. For example, referring to FIG. 3, the air plenum member 16 may be in fluid communication with a fan 41 that provides temperature conditioned air and/or cabin air to the air plenum member 16. More specifically, the fan 41 may provide temperature conditioned air and/or cabin air through the passage 28 and to the air plenum member 16, which may then route the air to the trim cover 22 such that the air may pass through the trim cover 22 and to a seat occupant. In this way, the fan 41 may function as a positive pressure source that is coupled to the air plenum member 16.

The fan 41 may be provided as part of the seat assembly 10, or the fan 41 may be a separate component that is mounted to the vehicle proximate to or remotely from the seat assembly 10. In the embodiment shown in FIG. 3, for example, the fan 41 is mounted to the support member 18 of the seat bottom 12.

Temperature conditioned air may be provided by a heating and/or cooling element 42, such as a Peltier element or other thermoelectric device, that is mounted to the seat assembly 10, such as to the support member 18, or to the vehicle. As another example, temperature conditioned air may be provided by a vehicle heating, ventilating and air-conditioning system (HVAC system, not shown) that is coupled to the air plenum member 16 by a duct (not shown).

In addition, or as an alternative, the fan 41 may be configured to draw cabin air through the trim cover 22 and into the air plenum member 16. More specifically, the fan 41 may function as a negative pressure source that is coupled to the air plenum member 16 via the passage 28. When activated, the fan 41 may draw cabin air through the trim cover 22, into the air plenum 16, and then through the passage 28.

The trim cover 22 may be made of any suitable material that is sufficiently permeable to allow air to pass therethrough. For example, the trim cover 22 may comprise an appearance or contact layer 44 made of air-permeable fabric, perforated vinyl, and/or perforated leather. The trim cover 22 may also be provided with or without a permeable padding layer 46, such as a permeable foam layer.

Furthermore, a heating element 48 may be integrated into the trim cover 22 if desired. For example, the heating element 48 may be bonded to an underside of the padding layer 46, or sandwiched between the contact layer 44 and padding layer 46. As another example, the heating element 48 may be provided as a separate component that is positioned between the trim cover 22 and air plenum member 16.

The seat bottom 12 may also include one or more additional layers (not shown) positioned between the air plenum member 16 and the trim cover 22. For example, the seat bottom 12 may include an additional permeable padding layer, such as a foam layer (not shown), and/or a sensor mat (not shown) for detecting the presence of a seat occupant.

Referring to FIGS. 2-5, a method of making the seat bottom 12 of the seat assembly 10 will now be described, with the understanding that the seat back 14 may be made in the same or similar manner. The method involves forming the portions 36 and 38 of the air plenum member 16 in any suitable manner. For example, the first portion 36 may be formed of air-impermeable, sufficiently rigid foam that is molded into a desired shape, and the second portion 38 may be die cut from a roll of flexible plastic material, such as a roll of non-woven polypropylene fibers, polypropylene film, or polyethylene film.

Next, the portions 36 and 38 may be positioned together and attached together such that the second portion 38 overlaps edges of the first portion 36. The portions 36 and 38 may be attached together in any suitable manner to provide a sufficient seal between the portions 36 and 38. In one embodiment, the method involves heat staking the second portion 38 to the first portion 36 such that the portions 36 and 38 fuse together and form a seal along a junction of the portions 36 and 38. Referring to FIG. 5, for example, the portions 36 and 38 may be vibration welded, sonic welded, or otherwise heat fused together using an attachment apparatus, such as welding apparatus 49. Such an attachment means provides a highly durable connection between the portions 36 and 38, and may also provide an air-tight seal along the entire junction of the portions 36 and 38.

The second portion 38 may also be trimmed if desired to reduce or eliminate any overhang of the second portion 38 relative to the first portion 36. As another example, the second portion 38 may be configured to extend between adjacent branches 32 of the air plenum member 16.

Referring to FIGS. 3 and 4, the air plenum member 16 may then be positioned in the recess 24 of the seat cushion 20 such that an opening 50, which may be an inlet or an outlet of the air plenum member 16, depending on the direction of air flow, is in fluid communication with the passage 28. The air plenum member 16 may also be attached to the seat cushion 20 if desired. For example, the air plenum member 16 may be adhesively bonded to the seat cushion 20.

The seat cushion 20 may be mounted on the support member 18 before or after the air plenum member 16 is positioned in the recess 24. Furthermore, the fan 41, heating and/or cooling element 42 and associated ducts, if included, may be mounted to the support member 18 at any suitable time. The method next involves positioning the trim cover 22 over the air plenum member 16, support member 18, and seat cushion 20.

The use of polypropylene in the second portion 38 of the air plenum member 16 may provide several advantages. For example, polypropylene resists shrinkage at high temperatures. In addition, polypropylene is highly stable and resists hydrolysis. Polypropylene may also be readily heat bonded to the first portion 36.

While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. 

1. A seat assembly comprising: a seat cushion having a recess; an air plenum member disposed in the recess for routing air through at least a portion of the seat cushion, the air plenum member including a first portion that comprises foam, and a second portion that is attached to the first portion and that comprises a polyolefin sheet; and a cover layer covering the air plenum member and the seat cushion.
 2. The seat assembly of claim 1 wherein the polyolefin sheet comprises polypropylene.
 3. The seat assembly of claim 1 wherein the polyolefin sheet comprises polypropylene fibers.
 4. The seat assembly of claim 1 wherein the polyolefin sheet comprises a polypropylene film.
 5. The seat assembly of claim 1 wherein the first portion is a bottom portion of the air plenum member, and the second portion is a top portion of the air plenum member.
 6. The seat assembly of claim 1 wherein the second portion is heat staked to the first portion such that a seal is formed along at least a portion of a junction of the first and second portions.
 7. The seat assembly of claim 1 wherein the second portion has multiple apertures for passing air through the second portion.
 8. The seat assembly of claim 1 wherein the foam of the first portion is air-impermeable.
 9. A seat assembly comprising: a seat cushion having a recess; an air plenum member disposed in the recess for routing air through at least a portion of the seat cushion, the air plenum member including a first portion that comprises foam, and a second portion that comprises a plastic sheet heat staked to the first portion such that the second portion is fused with the first portion, thereby forming a seal along at least a portion of a junction of the first and second portions; and a cover layer covering the air plenum member and the seat cushion.
 10. The seat assembly of claim 9 wherein the second portion comprises polypropylene.
 11. The seat assembly of claim 9 wherein the second portion comprises polypropylene fibers.
 12. The seat assembly of claim 9 wherein the second portion comprises a polypropylene film.
 13. The seat assembly of claim 9 wherein the second portion comprises polyethylene.
 14. The seat assembly of claim 9 wherein the first portion is a bottom portion of the air plenum member, and the second portion is a top portion of the air plenum member.
 15. A method of making a seat assembly, the method comprising: positioning together first and second portions of an air plenum member, the first portion comprising foam and the second portion comprising a plastic sheet; heat bonding the second portion to the first portion such that a seal is formed along at least a portion of a junction of the first and second portions; positioning the air plenum member in a recess of a seat cushion; and positioning a cover layer over the air plenum member and the seat cushion; wherein the air plenum member is configured to route air through at least a portion of the seat cushion.
 16. The method of claim 15 wherein the second portion comprises polypropylene.
 17. The method of claim 15 wherein the second portion comprises polypropylene fibers.
 18. The seat assembly of claim 15 wherein the second portion comprises a polypropylene film.
 19. The method of claim 15 wherein the second portion comprises polyethylene.
 20. The method of claim 15 wherein the first portion is a bottom portion of the air plenum member, and the second portion is a top portion of the air plenum member. 